Removable electrical connector filter assembly



N. H. CAMIRE Nov; 10, 1970 REMOVABLE ELECTRICAL CONNECTOR FILTER ASSEMBLY Filed July 29, 1969 2 Sheets-Sheet l INVENTOR A OEMAA/ H CAM/6 syj wj/g? A TTOE/VV v 2 Sheets-Sheet 2 INVENTOR A/OEM/I/V H CAM/66 M. Q m g 3 w& N w% M MU N 4 N. H. CAMIRE REMOVABLE ELECTRICAL CONNECTOR FILTER ASSEMBLY Filed July 29, 1969 United States Patent ace U.S. Cl. 333-79 5 Claims ABSTRACT OF THE DISCLOSURE A removable electrical connector filter assembly comprising an electrically conductive clip for mounting on a terminal pin member. The clip has a reduced central portion and adjacent enlarged portions with a spring member externally secured to each of the enlarged portions. An electrical filter member formed of dielectric material has a conductive inner surface portion removably secured on the clip with the spring members secured to the filter member inner surface. The terminal pin member may contain a reduced diameter central undercut portion, the clip being removably mounted on the terminal pin member with the reduced central portion of the clip being normally secured to the terminal pin member undercut portion.

The invention relates in general to removable electrical connector filter assemblies, and, more particularly, to a snap-in filter element for use in coaxial lines.

BACKGROUND OF THE INVENTION Typical removable electrical connector filters are depicted in U.S. patent application 55,398 filed June 6, 1966, now Pat. No. 3,462,715; U.S. patent application 793,264 filed Jan. 23, 1969, and U.S. patent application 819,692 filed Apr. 28, 1969. In each of these patent applications, means are provided for slidably moving a filter member along a terminal pin so that the filter is easily removable from the pin. When the filter is placed on the terminal pin, it has been found that damage would occur should the filter be incorrectly positioned on the terminal pin for mounting on a final assembly, such as in an insulator housing. Moreover, should the filter move, it has been found that the filter characteristics could vary suiiiciently to cause adverse operation of the circuit to which the filter is connected. Further, the slidable filter would vary in the amount of strength needed to remove the filter from the terminal pin and thus damage might occur, should overexertion be required in moving the filter.

In order to overcome the attendant disadvantages of prior art removable electrical connector filters, the present invention provides a relatively simple filter assembly which is positioned on an electrical terminal member in a positive manner. The filter assembly can be used as a self-centering device and a transfer device for attaching of a filter tube to the contact. Moreover, the assembly is adaptable to terminal pins having different cross sections.

The advantages of this invention, both as to its construc tion and mode of operation will be readily appreciated as the same become better understood by reference to the following detailed description when considered in connection with the accompanying drawings in which like referenced numerals designate like parts throughout the figures.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 depicts the removable electrical filter assembly disassembled prior to mounting on a terminal pin; and

FIG. 2 depicts the filter assembly of FIG. 1 on the terminal pin and mounted in a connector assembly.

Patented Nov. 10, 1970 DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is shown in FIG. 1, an electrical connector filter assembly in accordance with the invention. The assembly comprises a ceramic tubular filter member 10 made up of a high dielectric constant material such as barium titanate. The member 10 is coated on its inner surface by 'a conductive layer 12 such as a silver frit which extends around the ends of the member 10 and covers the outer end portion thereof. Further, the outer central surface of the member 10 contains a conductive layer 14 which is separated from the outer end portion of the layer .12 by air gaps 16 and 18.

An electrically conductive clip 22 is formed of a central portion 24 and a pair of end portions 26, 28. The central portion 24 may be of spring-like material and have a reduced diameter as compared to the adjacent portions 26, 28. A longitudinal seam 32 is formed along the clip. The portions 26 and 28 contain, at its outer ends, spring-like members 34, 36, respectively, folded back along its edges. Along the outer end surface of the spring-like members 34, 36 there may be formed ears 40, 42. The spring-like members 34, 36 may be compressed slightly so that the diameter of the clip 22 is reduced sufficiently so as to allow the clip to pass through the inner surface of the member 10. Once the clip has been centered in the tube 10, pressure on the springs 34, 36 may be released so as to enable the ears 40, 42 to abut the end portions of the member 10.

An electrical terminal member 44 contains a front square cross-sectional contacting portion 46 and a rear square cross-sectional contacting portion 48 which are interconnected by a circular undercut portion 52, whose diameter is slightly smaller that the diagonal of the portions 46, 48. The terminal member further comprises a shoulder 54 which is secured to a transitional portion 56 at the rear end of the square contacting portion 48. Further, the rear end of the shoulder is connected to a flat tab member 58 whose width is equal to the width of the shoulder 54 at the front end 62 thereof, and has a reduced width 64 at the rear end thereof. At the enlarged portion 62, there is formed a tang member 66 whose purpose will be explained hereinafter. The portion 24 of the clip 22 is secured to the undercut 52 and forms a position stop when the clip is slipped over the terminal. A slight force is necessary to remove the clip from the terminal and in its normal use, the clip has suflicient spring-like qualities to positively secure the clip to the terminal.

Referring now to FIG. 2 there is shown the electrical filter assembly of FIG. 1 assembled and mounted on the terminal pin and the entire assembly mounted on a connector block. The connector block is formed of a rear dielectric block portion 82, and a front dielectric block portion 84. The rear portion 82 contains counter bores 86 which open to the rear of the block and are contiguous at the front end thereof with a reduced diameter portion 88. Further, a threaded bore portion 92 is formed in the rear end of the forward block 84 and forms a continuation of the bore 88 so as to allow bolts 94 to be inserted through the counter bore 86 and secure the block 82 to the block 84 when inserted in the bores 88 and 92.

The rear block 82 contains an enlarged rear bore 102 and a reduced diameter forward bore :104. A rearward facing shoulder 106 is formed at the junction of the bores 102 and 104. At the front end of the bore 104 there is formed a forward facing shoulder 108. Further, a slight flared opening 110 commences at the front end of the outer surface of the bore 104 and terminates at the front surface of the block 82.

The block 84 contains an enlarged forward bore 114 which terminates at the front end of the block in a flared opening 116. The rear end of the block 84 contains a tapered bore 118 which forms a continuation of the flared opening 110 of the block 82 and which is a maximum width at its junction at the rear end fo the bore 114. The entire block 84 is aluminum plated along the bore surfaces 114 and 118 as well as along the outer surfaces of the block 84 to form a grounding plane.

After the filter member 10 has been mounted on the clip 22 and the terminal member 44 inserted in the clip 22, a dielectric insulator bushing 122 is slipped over the front end of the terminal pin. The bushing 122 is cupshaped and contains a front wall 124 having an opening 126 therethrough through which the portion 46 of the terminal member extends and a side wall 128 integral with the front wall 124. An annular groove 132 is cut into the outer surface of the side wall of the bushing at the center thereof. Further, the inner surface of the side wall 128 contains an enlarged rear diameter bore 134 and a reduced diameter forward bore 136. A ground spring 142 is secured to the bushing and comprises a cylindrical shaped shell having a lip 144 at its front end which extends into and is secured in the groove 132. The ground spring 142 contains a front end portion 146 which extends from the lip 144 rearwardly along the outer surface of the bushing 128 and contains an outward bowed portion 148 whose outer surface contacts the aluminum plated bore 120 of the block 84. Further, the bowed portion terminates inwardly at the rear end 152 thereof, the inner surface thereof being secured to the outer central layer 14 of the filter.

The entire filter assembly including the bushing 128 and spring 148 are inserted through the front end of the block 84 and the tang member 66 of the terminal member 44 is depressed inwardlly so as to allow the terminal member to pass through the bore 104. When the tang member 66 has passed through the bore 104, it is released automatically and the front end thereof abuts the rearward facing shoulder 106, preventing the terminal member from moving in a forward direction. Further, the shoulder 54 prevents the assembly from movement in a rearward direction.

Further, while the filter member 10 has been depicted as a capacitor connected between the terminal member and ground, it should be understood that other arrangements are possible. For example, the filter could be a pifilter as depicted in the previously mentioned patent applications.

What is claimed is:

1. A removable electrical filter assembly comprising:

an electrically conductive clip for mounting on a terminal pin member, said clip having a reduced central portion and adjacent enlarged portions, a spring member externally secured to each of said enlarged portions; and

an electrical filter member formed of dielectric material having a conductive inner surface portion removably secured on said clip wherein said spring members are secured to said filter member inner surface.

2. A removable electrical filter assembly in accordance with claim 1 wherein said filter member is cylindrically shaped and wherein said spring members have outwardly extending portions along the outer ends thereof which abut the ends of said filter member when said filter member is counted on said clip.

3. A remova'ble electrical filter assembly in accordance with claim 1 wherein said spring member may be depressed inwardly for mounting and removing said filter member from said clip.

4. A removable electrical filter assembly in accordance with claim 1 wherein said terminal pin member contains a reduced diameter central undercut portion, said clip being removably mounted on said terminal pin member with said reduced central portion of said clip being normally' secured to said terminal pin member undercut portion.

5. A removable electrical filter in accordance with claim 4 wherein said terminal member contains means for preventing axial movement of said assembly when mounted in a connector assembly.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,539 Dated November 10 1970 Norman H. Camire Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, line 19, "counted" should read mounted Signed and sealed this 13th day of April 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, Attesting Officer Commissioner of Pater FORM PO-IOSD (10-69) 

